Winding machine for groups of packages

ABSTRACT

Machine for winding a load by means of an extensible web, comprising a fixed plane for supporting the load, a fixed framework overlying said plane, a framework moveable vertically on the fixed framework, which rotatably supports a horizontal circular guide, means for rotating the guide, means for imposing vertical translations to the moveable framework, means suspended on said guide bearing the reel with the winding web, in which the circular guide has a hollow tubular section, and is rotatably held within a seat integral with moveable framework and comprising at least three pairs of wheels with mutually inclined axes for creating the seat for sliding and retaining the guide.

The present invention refers to machines adapted to wind regular groupsof objects arranged on a pallet using an extensible web.

Regarding transport of groups of palletized objects, there are woundgroups of objects by means of a web which is stretched during thewinding with the aim of making each group appropriate, and stabilise theload of the pallet. The web is wound around the load of the pallet in ahelical manner so as to cover the entire height of the load.

The number of turns of the winding depends on the height of the web,besides the height of the load. The machines adapted to wind the web aresubstantially of two types.

A first type of machine comprises a rotating platform on which the loadto be wound is arranged, beside which there are arranged fixed means forsupporting the reel of the stretchable web.

These means are provided with a vertical motion so that, due to therotation of the load and the vertical movement of the reel, the web iswound helically on the load.

The machines of this type reveal the drawback lying in the fact thatwhen the load of the pallet is made up of several layers of poorlystable objects, for example bottles, when rotated, the load tends tocrumble under the action of the centrifuge force, and thus the machinemay function solely at a relatively low speed of rotation of the load,to the detriment of the production capacity thereof.

A second type of known machines provides for that the load remainsstationary, and that the reel be guided to cover a helical path aroundthe load.

This type of machines comprises: a fixed plane for supporting the load,a fixed framework overlying said plane, a framework moveable verticallyon the fixed framework, which rotatably supports a horizontal circularguide, means for rotating the guide, means for imposing verticaltranslations to the moveable framework, means rigidly suspended on saidguide bearing the reel with the winding web.

The suspension means comprise a framework with vertical axis on whichthere is arranged the hub supporting the reel.

There are provided means which adjust the winding of the reel and conferthe necessary tension to the web.

This type of machine has a winding speed limit given that the centrifugeforce to which the means are subjected, rigidly suspended on said guidebearing the reel with the winding web, and the respective reel,complicates the action of maintaining the reel with the rigorouslyvertical axis, which is essential for a correct winding of the reel onthe load.

The drawback derives from the torsional deformation to which thecircular guide—to which there are rigidly suspended means bearing thereel with web—is locally subjected, forcing to reduce the maximum axialdimensions of the reel and consequently the weight of the frameworkwhich supports it.

Machines of this type suitable for using reels having an axial dimensiongreater than 750 mm, and rotate at more than 40 rpm are not currentlyknown.

The axial dimension of the reel determines the number of windings forcovering a load of a given height and thus conditions the productioncapacity of the machine, given that the time for winding a load dependson the number of revolutions per minute that the reel can perform and onthe number of windings required to cover the load.

The object of the invention is to provide a winding machine of this typecapable of allowing operating at a winding speed comparatively greaterthan that of the known machines, simultaneously operating with reelshaving an axial dimension comparatively greater than the axial dimensionof the reels used currently.

This object is attained by a machine having the characteristics listedin the independent claim. The dependent claims refer to subordinatecharacteristics adapted to confer further advantages to the invention.

The winding machine according to the invention comprises a circularguide with tubular section, i.e. a hollow and closed section.

The guide has preferably a circular section (for example internally soas externally), but it could be square, triangular orirregular-sectioned (for example, only internally).

The guide is rotatably held in a seat fixed to the moveable framework,which comprises at least three peripheral pairs of wheels, equallyspaced on a circumference, which have the axes mutually inclined forcreating the seat for sliding and retaining the guide.

In a preferred solution each pair of wheels may be replaced by a groupof pairs of adjacent wheels, the groups being fixed to the moveableframework in an equally spaced position on a circumference.

In the case in which the horizontal guide has a circular section(externally), it comprises—on the outer side—two flat elementsconverging on the horizontal symmetry plane, which serve as a slidingtrack for the wheels which constitute the seat for sliding and retainingthe guide.

At least one bracket removably supporting the means bearing the reelwith web is rigidly fixed to the guide.

The brackets rigidly connected to the guide, should they be more thanone, are equally spaced to allow simultaneously winding several webs onthe load.

The at least one bracket comprises a vertical plane to which there arefixed the detachable means which support the at least one reel with webto be wound in vertical position.

The construction and functional characteristics of the invention will beapparent from the detailed description that follows, with reference tothe figures of the attached drawings illustrating a preferred embodimentprovided by way of non limiting example.

FIG. 1 shows a perspective view of the machine.

FIG. 2 shows a front view of the machine, from the direction II of FIG.1.

FIG. 3 shows the section III-III of FIG. 2.

FIG. 4 shows the section IV-IV of FIG. 2.

FIG. 5 shows the section V-V of FIG. 4.

FIG. 6 shows an enlarged detail of FIG. 5.

FIG. 7 shows the section VII-VII of FIG. 4.

The figures show a bridge framework 1, with square-shaped base, which istraversed by a roller track 2 on which the load to be wound travels soto be arranged in a winding station at the centre of the framework 1.

Within the framework 1 the roller track constitutes the stationaryplatform of the load during the winding.

The framework 1 comprises four uprights respectively 11, 12, 13 and 14which serve as a guide for a horizontal framework 3 which is suspendedwith four belts 31, arranged within the uprights, for moving vertically,upon the action of the motors 32.

The framework 3 supports by means of at least three brackets 33,preferably six only two of which are illustrated in FIG. 3, and six areillustrated in FIG. 7, a circular guide 4 with circular section, whichis free to rotate (FIG. 3).

Each bracket 33 supports a body which comprises three pairs of idlewheels 340, having the inclined axes.

The guide 4 has two symmetric circular flat elements 41, which serve asrolling tracks for the wheels 340, between which the guide 4 is slidablysupported.

The electric motor 34 which actuates a pulley 35 (FIG. 3) on whosegroove there is wound a belt 36 is fixed to the framework 3.

The belt 36 is closed loop-like to the guide 4 and it is wound betweenthe flat elements of the same driving it in rotation.

The guide 4 has at least one lower bracket 42 (FIGS. 5 and 6) by meansof the brackets 45, which carries a horizontal plane 43 to which themeans 44 for supporting the framework 5 which carries the reel 51 areremovably fixed.

The framework 5 is of the known type and it is not described in detail.

The means 44 are also of the known type, and they are adapted to receivea vertical tang of the framework 5 for carrying the reel, blocking it bymeans of known means neither described in detail nor illustrated.

At the base of the framework 1, in one of the two sides parallel to thetrack 2, there are arranged two parallel horizontal guides 61 and 62,shown solely in FIG. 1, which extend in symmetric position with respectto a diametric plane of the guide 4.

On each of the guides 61 and 62 there may slide, supported by means notillustrated, a framework 5 for carrying the reels to be placed between aposition distant from the guide 4 in which the frameworks 5 arecollected with the finished reel 51, at a position beneath the guide 4in which the frameworks are seized and blocked by the means 44.

The framework 5 for carrying the reel 51 is made up of an upper plate 52and a lower plate 53 connected by spacers not illustrated, usual webtensioning means; the means on which the reel 51 is arranged are derivedfrom the plates.

The motor 35 which rotates the guide 4 and the motors designated for thevertical translation thereof are controlled by a microprocessor, notillustrated, which actuates them synchronously so that they helicallywind the reel on the load arranged on the roller tracks 2.

The circular section configuration of the guide 4 confers to the same ahigh torsional resistance which efficiently counters the momentgenerated by the centrifuge force, operating on the framework 5 and onthe reel 51, preventing displacements thereof towards the external whichwould damage the correct tensioning in the web which is unwound from thereel 51.

The torsional deformations are further hindered by the action of thewheels 340 on the flat elements 41 of the guide.

The aforementioned characteristics allow operating with reels having anaxial length of 1,000 mm, 30% greater than the usual one, and at awinding speed up to 70 rpm, almost twice the usual speed.

The invention shall be deemed not limited to the described example andit may be subjected to variants and improvements without departing fromthe scope of protection of the claims that follow.

1. Machine for creating at least one helical winding for a webextensible around a load, comprising a stationary plane for supportingthe load, a fixed framework overlying said plane, a framework overlyingthe moveable load vertically on the fixed framework, which rotatablysupports a horizontal circular guide rotated with respect to theframework moveable by suitable means, means for imposing verticaltranslations to the moveable framework, means rigidly suspended on saidguide bearing the reel with the winding web, wherein the circular guidehas a tubular section, and it is slidable within a seat integral withmoveable framework constituted by at least three groups for sliding andsupporting the guide, placed circumferentially equally spaced and eachprovided with at least one pair of wheels with mutually inclined axesfor creating the seat for sliding and retaining the guide, characterisedin that the guide is a hollow circular section and comprises—insymmetric positions with respect to the horizontal median plane of theguide—two flat elements which serve as a sliding seat for the pairs ofwheels.
 2. Machine according to claim 1 characterised in that each groupconstituting the sliding seat of the guide comprises at least two groupsof pairs of wheels with mutually inclined axes for creating the seat forsliding and retaining the guide.
 3. Machine according to claim 1characterised in that the means for rotating the guide with respect tothe moveable framework are constituted by an electric motor on whoseaxis there is arranged a pulley on whose groove there is wound aflexible means closed loop-like which is also wound on the periphery ofthe guide between the pairs of wheels with mutually inclined axes whichcreate the seat for sliding and retaining the guide with respect to themoveable framework.
 4. Machine according to claim 1 characterised inthat each group is arranged on a bracket integral with the moveableframework.
 5. Machine according to claim 4 characterised in that itcomprises six brackets each provided with three pairs of wheels.